#3 was built in 1952, serial #5622, model M.D.T. type 2, by Plymouth Locomotive Company of Plymouth, Ohio and is powered by a Caterpillar D337 inline 6-cylinder diesel engine. It weighs 30 tons on two axle drivers. The locomotive was donated to Mid-Continent by Wisconsin Power & Light in 1987. The locomotive is currently on loan to the Circus World Museum, at Baraboo, Wisconsin where it is used for switching.